Just days old, Apple's Safari for Windows is already proving it can tempt Microsoft users to flirt with a new browser, even as Cupertino unleashes its first batch of security updates.

Apple has confirmed that its new Safari 3 for Windows browser, launched by Steve Jobs on Monday at the Mac manufacturer's annual worldwide developers' shindig, has hit one million downloads already.

According to Apple, the browser reached the landmark one million figure in the first 48 hours after release. Despite its seven-figure downloads, Safari for Windows is a long way off the glory of Apple's biggest Mac-to-PC crossover hit, iTunes, which has been downloaded over 500 million times by Windows users.

Apple claims the Safari 3 browser, which is compatible with Vista and XP as well as Mac systems, is the fastest surfing software for Windows.

The cross-platform browser is likely to give Jobs' company a leg-up in the browser stakes, where it remains dwarfed by Microsoft and the Mozilla Foundation's products. According to figures cited by Apple, Safari has just five percent of the browser market compared to IE's almost 80 percent and Firefox's 15 percent.

It may have picked up one million new users, but the browser has also seen some security issues come to light since its release earlier this week.

Within hours of its launch, security watchers had spotted vulnerabilities in the software, which Apple has now moved to plug. Three patches are available for the browser through Apple's Software Update application.

The vulnerabilities could allow an attacker to execute code on a machine using the Windows Safari browser if a user visits a malicious Web site. Only one of the flaws affect Mac systems but it poses no security threat, Apple said in an advisory.